How Does Evolution Take Place?

Aditi says, how does ev on take place? What causes our biology to evolve? Our journey to becoming homo sapients? How does it take place at the atomic level? Please give your views on the ancient girl who was an interbred of nandethas and denisoons. Is interbreting possible to day? And do there exist these species in pure form anywhere somewhere in the world,. So what is evolution? Evolution is a very slow process. It doesn't happen or a period of weeks or hours or months or years. It happens over hundreds of thousands of years.